The Mode of Action of 6-Methoxy-1,2,3,4-Tetrahydro-β-Carboline on Brain Serotonin

1973 ◽  
Vol 51 (4) ◽  
pp. 482-485 ◽  
Author(s):  
Beng T. Ho ◽  
Dorothy Taylor ◽  
K. E. Walker ◽  
William M. McIsaac
Keyword(s):  
Monoamine Oxidase ◽  
Rat Brain ◽  
Mouse Brain ◽  
Rat Liver ◽  
Mode Of Action ◽  
Tryptophan Hydroxylase ◽  
Rat Plasma ◽  
Concomitant Increase ◽  
Tryptophan Pyrrolase ◽  
The Brain

6-Methoxy-1,2,3,4-tetrahydro-β-carboline (6-MeO-THBC), which specifically elevates serotonin in the brain, exerted no significant effects on mouse brain monoamine oxidase, rat brain tryptophan hydroxylase, and rat liver tryptophan pyrrolase. There was a marked activation of rat plasma and liver 5-hydroxytryptophan decarboxylase and a concomitant increase of serotonin levels in the two tissues. 6-MeO-THBC did not alter the endogenous tryptophan levels in rat plasma and brain. A significant facilitation of the uptake of [3-14C]-5-hydroxytryptophan was observed in brains of mice treated with 6-MeO-THBC. The possibility that the increased serotonin was derived from 6-MeO-THBC itself was ruled out.

The effects of hashish components and their mode of action on monoamine oxidase from the brain

1978 ◽  
Vol 27 (21) ◽  
pp. 2513-2517 ◽  
Author(s):  
Avital Schurr ◽  
Ofra Porath ◽  
Margalith Krup ◽  
Avinoam Livne
Keyword(s):  
Monoamine Oxidase ◽  
Mode Of Action ◽  
The Brain

scholarly journals Enhancement of rat brain tryptophan metabolism by chronic ethanol administration and possible involvement of decreased liver tryptophan pyrrolase activity

1979 ◽  
Vol 178 (3) ◽  
pp. 575-580 ◽  
Author(s):  
A A Badawy ◽  
N F Punjani ◽  
M Evans
Keyword(s):  
Methylene Blue ◽  
Rat Brain ◽  
Chronic Ethanol ◽  
Tryptophan Metabolism ◽  
Ethanol Administration ◽  
Chronic Ethanol Administration ◽  
Tryptophan Pyrrolase ◽  
Tryptophan Concentration ◽  
Phenazine Methosulphate ◽  
The Brain

1. Chronic ethanol administration enhances rat brain 5-hydroxytryptamine synthesis by increasing the availability of circulating tryptophan to the brain. This increased availability is not insulin-mediated or lipolysis-dependent. 2. Under these conditions, tryptophan accumulates in the liver and apo-(tryptophan pyrrolase) activity is completely abolished, but could be restored by administration of regenerators of liver NAD+ and/or NADP+. 3. All four regenerators used (fructose, Methylene Blue, phenazine methosulphate and sodium pyruvate) prevented the ethanol-induced increase in liver tryptophan concentration and the increased availability of tryptophan to the brain. 4. It is suggested that the enhancement of brain tryptophan metabolism by chronic ethanol administration is caused by the decreased hepatic tryptophan pyrrolase activity. The results are briefly discussed in relation to previous work with ethanol. 5. Fructose enhances the conversion of tryptophan into 5-hydroxyindol-3-ylacetic acid in brains of ethanol-treated rats, whereas Methylene Blue inhibits this conversion in both control and ethanol-treated animals.

scholarly journals Pathway in rat brains under experimental obesity caused long-term progesterone administration

2018 ◽  
Vol 75 (1) ◽  
pp. 59-63
Author(s):  
A. Aleksandrov ◽  
V. Konopelniuk ◽  
I. Kompanets ◽  
L. Ostapchenko
Keyword(s):  
Rat Brain ◽  
Tryptophan Hydroxylase ◽  
The Body ◽  
Control Group ◽  
Tryptophan Decarboxylase ◽  
Decarboxylase Activity ◽  
Prolonged Administration ◽  
Hydroxyindoleacetic Acid ◽  
The Brain

Obesity is one of the most common complex health problem. The pathway of serotonin synthesis takes part in neuroendocrine regulation, as well as in the regulation of a number of behavioral functions of the body and fat deposition. Serotonin is a mediator of the amine nature, which functions as a neurotransmitter and tissue hormone. The greatest amount of serotonin is synthesized in the brain and 12 duodenum. As a neurotransmitter, serotonin affects both directly and indirectly on the function of most brain cells. Female hormone progesterone influence on serotonin functions. One of the effect of progesterone is increasing of amount of fat tissue during the pregnancy. Long-term using of progesterone in hormone substitution therapy or as part of contraception also lead to fat accumulation effect. The levels of activity of serotonergic system enzymes, tryptophan hydroxylase, tryptophan decarboxylase and monoamine oxidase (MAO), and tryptophan, 5-hydroxytryptophan, serotonin and 5-hydroxyindoleacetic acid concentrations in the rat brain under obesity conditions caused by prolonged administration of progesterone were determined in this study. Studies have shown that the content of tryptophan, 5-hydroxytryptophan, serotonin and 5-hydroxyindoleacetic acid in the brain of rats under obesity caused by prolonged administration of progesterone increased in comparison with the rats of the control group. The levels of tryptophan hydroxylase and MAO activity decreased, and tryptophan decarboxylase activity levels increased in the rat brain under obesity conditions caused by prolonged administration of progesterone. Thus, as a result of our studies, we found an imbalance in the system of serotonin metabolism in the brain of rats with the development of hormonal obesity induced by prolonged administration of progesterone, which may indicate the involvement of the serotonergic neurotransmitter system in the mechanisms of the development of obesity and concomitant diseases.

scholarly journals Inhibition of rat brain tryptophan metabolism by ethanol withdrawal and possible involvement of the enhanced liver tryptophan pyrrolase activity

1980 ◽  
Vol 192 (2) ◽  
pp. 449-455 ◽  
Author(s):  
A A B Badawy ◽  
N F Punjani ◽  
C M Evans ◽  
M Evans
Keyword(s):  
Rat Brain ◽  
Ethanol Withdrawal ◽  
Chronic Ethanol ◽  
Tryptophan Metabolism ◽  
Ethanol Administration ◽  
Time Intervals ◽  
Chronic Ethanol Administration ◽  
Tryptophan Pyrrolase ◽  
The Brain ◽  
Withdrawal Phase

1. Chronic ethanol administration to rats was previously shown to enhance brain 5-hydroxytryptamine synthesis by increasing the availability of circulating tryptophan to the brain secondarily to the NAD(P)H-mediated inhibition of liver tryptophan pyrrolase activity. 2. At 24h after ethanol withdrawal, all the above effects were observed because liver [NAD(P)H] was still increased. By contrast, all aspects of liver and brain tryptophan metabolism were normal at 12 days after withdrawal. 3. At 7–9 days after withdrawal, brain 5-hydroxytryptamine synthesis was decreased, as was tryptophan availability to the brain. Liver tryptophan pyrrolase activity at these time-intervals was maximally enhanced. 4. Administration of nicotinamide during the withdrawal phase not only abolished the withdrawal-induced enhancement of tryptophan pyrrolase activity on day 8, but also maintained the inhibition previously caused by ethanol. Under these conditions, the withdrawal-induced decreases in brain 5-hydroxytryptamine synthesis and tryptophan availability to the brain were abolished, and both functions were enhanced. Nicotinamide alone exerted similar effects in control rats. 5. It is suggested that ethanol withdrawal inhibits brain 5-hydroxytryptamine synthesis by decreasing tryptophan availability to the brain secondarily to the enhanced liver tryptophan pyrrolase activity. 6. The results are discussed in relation to the possible involvement of 5-hydroxytryptamine in dependence on ethanol and other drugs.

scholarly journals Changes in ornithine decarboxylase and antizyme activities in developing mouse brain

1988 ◽  
Vol 250 (3) ◽  
pp. 797-803 ◽  
Author(s):  
H Onoue ◽  
S Matsufuji ◽  
M Nishiyama ◽  
Y Murakami ◽  
S Hayashi
Keyword(s):  
Monoclonal Antibodies ◽  
Ornithine Decarboxylase ◽  
Mouse Brain ◽  
Rat Liver ◽  
Developmental Period ◽  
Kinetic Properties ◽  
Antizyme Inhibitor ◽  
Developing Mouse Brain ◽  
The Brain

A macromolecular inhibitor to ornithine decarboxylase (ODC) present in mouse brain was identified as ODC antizyme [Fong, Heller & Canellakis (1976) Biochim. Biophys. Acta 428, 456-465; Heller, Fong & Canellakis (1976) Proc. Natl. Acad. Sci. U.S.A. 73, 1858-1862] on the basis of kinetic properties, Mr and reversal of its inhibition by antizyme inhibitor. The brain antizyme, however, did not cross-react immunochemically with any of seven monoclonal antibodies to rat liver antizyme. ODC activity in mouse brain rapidly decreased after birth, in parallel with putrescine content, and almost disappeared by 3 weeks of age. Free antizyme activity appeared shortly after birth and increased gradually, whereas ODC-antizyme complex already existed at birth and then gradually decreased. Thus total amount of antizyme remained about the same throughout the developmental period in mouse brain. In addition to ODC-antizyme complex, inactive ODC protein was detected by radioimmunoassay in about the same level as the complex at 3 weeks of age. Upon cycloheximide treatment, both free ODC activity and ODC-antizyme complex rapidly disappeared, although free antizyme and the inactive ODC protein were both quite stable.

N-Acylation of tyramines: purification and characterization of an arylamine N-acetyltransferase from rat brain and liver

1979 ◽  
Vol 57 (10) ◽  
pp. 1204-1209 ◽  
Author(s):  
Peter H. Yu ◽  
Alan A. Boulton
Keyword(s):  
Monoamine Oxidase ◽  
Rat Brain ◽  
Kinetic Parameters ◽  
Biogenic Amines ◽  
Significant Activity ◽  
Purification And Characterization ◽  
Rat Brain And Liver ◽  
The Brain ◽  
Optimal Ph

The N-acylation of tyramine isomers and other biogenic amines has been studied. The liver exhibits the highest activity towards tyramines, while the brain exhibits a low but significant activity. In the brain, tyramine N-acylation activity was heterogenously distributed. The arylamine N-acetyltransferase has been partially purified from both rat liver and brain, the two enzymes being quite similar with respect to their chromatographic properties, optimal pH requirement (pH 7.8), and their kinetic parameters. The product N-acetyltyramine is not oxidized by liver amidohydrolase or monoamine oxidase.

Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

1971 ◽  
Vol 29 ◽  
pp. 570-571
Author(s):  
E. A. Elfont ◽  
R. B. Tobin ◽  
D. G. Colton ◽  
M. A. Mehlman
Keyword(s):  
Chemical Composition ◽  
Rat Liver ◽  
Future Study ◽  
Mode Of Action ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Effective Inhibitor ◽  
Biochemical Effects ◽  
Glycerophosphate Dehydrogenase ◽  
Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

Inhibition of Rat Brain Monoamine Oxidase Activities by Psoralen and Isopsoralen: Implications for the Treatment of Affective Disorders

2001 ◽  
Vol 88 (2) ◽  
pp. 75-80 ◽  
Author(s):  
Ling Dong Kong ◽  
Ren Xiang Tan ◽  
Anthony Yiu Ho Woo ◽  
Christopher Hon Ki Cheng2Note
Keyword(s):  
Monoamine Oxidase ◽  
Rat Brain ◽  
Affective Disorders ◽  
Brain Monoamine

A Comparison of Plasminogen Activators Derived from Rat Plasma, Primary Rat Hepatocytes and Isolated Perfused Rat Liver

1982 ◽  
Vol 47 (02) ◽  
pp. 166-172 ◽  
Author(s):  
Yoav Sharoni ◽  
Maria C Topal ◽  
Patricia R Tuttle ◽  
Henry Berger
Keyword(s):  
Rat Liver ◽  
Isoelectric Point ◽  
Rat Hepatocytes ◽  
Cell Types ◽  
Plasminogen Activators ◽  
Rat Plasma ◽  
Isolated Perfused Rat Liver ◽  
Perfused Rat Liver ◽  
Molecular Weights ◽  
Physiological Relevance

SummaryOf the two cell types it was possible to culture from the dissociated rat liver, hepatocytes and Kupffer cells, only the former were fibrinolytically active. Rat hepatocytes during the first 24 hr in culture secreted two plasminogen activators with molecular weights identical to those found in rat plasma, an 80,000-dalton form (PA-80) and a 45,000-dalton form (PA-45). Partially purified preparations of plasminogen activators from both sources were subjected to isoelectric focusing (IEF) to compare characteristics further. There were three distinct peaks of PA-45 in each preparation with isoelectric points of 7.1, 7.2 and 7.4; all electrophoretic forms had the same low affinity to fibrin. PA-80 from both sources displayed similar IEF profiles with forms ranging from pH values of 7 to 8, all with the same high affinity to fibrin. The major form of PA-80 in the plasma preparation had an isoelectric point of 7.9 whereas that in the hepatocyte preparation had an isoelectric point of 7.6. The isolated perfused rat liver was also shown to produce both PA-80 and PA-45 emphasizing the physiological relevance of the findings with hepatocytes. It is concluded that in the rat hepatocytes contribute to the plasma profile with regard to the plasminogen activator content.

Liquid Chromatography Analysis of Clozapine in Rat Brain Tissue, Using its Molecularly Imprinted Polymer after Administration of Toxic Dose of Drug and Lipid Emulsion Therapy

2019 ◽  
Vol 15 (3) ◽  
pp. 251-257
Author(s):  
Bahareh Sadat Yousefsani ◽  
Seyed Ahmad Mohajeri ◽  
Mohammad Moshiri ◽  
Hossein Hosseinzadeh
Keyword(s):  
Rat Brain ◽  
Brain Tissue ◽  
Molecularly Imprinted Polymer ◽  
Lipid Emulsion ◽  
Limit Of Detection ◽  
Imprinted Polymer ◽  
Toxic Dose ◽  
Molecularly Imprinted ◽  
The Brain ◽  
Rat Brain Tissue

Background:Molecularly imprinted polymers (MIPs) are synthetic polymers that have a selective site for a given analyte, or a group of structurally related compounds, that make them ideal polymers to be used in separation processes.Objective:An optimized molecularly imprinted polymer was selected and applied for selective extraction and analysis of clozapine in rat brain tissue.Methods:A molecularly imprinted solid-phase extraction (MISPE) method was developed for preconcentration and cleanup of clozapine in rat brain samples before HPLC-UV analysis. The extraction and analytical process was calibrated in the range of 0.025-100 ppm. Clozapine recovery in this MISPE process was calculated between 99.40 and 102.96%. The limit of detection (LOD) and the limit of quantification (LOQ) of the assay were 0.003 and 0.025 ppm, respectively. Intra-day precision values for clozapine concentrations of 0.125 and 0.025 ppm were 5.30 and 3.55%, whereas inter-day precision values of these concentrations were 9.23 and 6.15%, respectively. In this study, the effect of lipid emulsion infusion in reducing the brain concentration of drug was also evaluated.Results:The data indicated that calibrated method was successfully applied for the analysis of clozapine in the real rat brain samples after administration of a toxic dose to animal. Finally, the efficacy of lipid emulsion therapy in reducing the brain tissue concentration of clozapine after toxic administration of drug was determined.Conclusion:The proposed MISPE method could be applied in the extraction and preconcentration before HPLC-UV analysis of clozapine in rat brain tissue.

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